Anderson, J.L. and J.M. Porter. 1994. Astragalus tortipes (Fabaceae), a new species
from desert badlands in southwestern Colorado and its phylogenetic relationships
within Astragalus. Systematic Botany 19(1): 116-125.

Kettler, S.M., N.D. Lederer, D. Bacher, and S. Spackman. 1993. Pike and San Isabel
National Forest and Comanche and Cimarron National Grasslands Plants of Special
Concern. Unpublished report prepared for the U.S. Forest Service.

Knight, P.J. 1981a. Rare, threatened, endangered and other plants of concern to
the Bureau of Land Management. Unpublished report.

Pavlick, L.E. and J. Looman. 1984. Taxonomy and nomenclature of rough fescues, Festuca
altaica, F. campestris, and F. hallii, in Canada and the adjacent United States.
Canadian Journal of Botany 62(8):1739-1749.

Peterson, J.S. and W.L. Baker. 1982. Inventory of the Piceance Basin, Colorado:
threatened and endangered plants, plant associations, and the general flora. Unpublished
report prepared for the Bureau of Land Management, Craig, CO.

Schwendinger, R.B., G.K. Carlson, and C.O. Spielman. 1991. Status report of Eutrema
penlandii as a result of field investigations in Park, Summit, Gunnison, Chaffee,
and Clear Creek counties. Unpublished report prepared for the U.S. Fish and Wildlife
Service, Golden, CO.

Sheviak, C.J. 1984. Spiranthes diluvialis (Orchidaceae), a new species from the
western United States. Brittonia 36:8-14.

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review of plant taxa for listing as endangered or threatened species. Federal Register
58(188):51144-51190.

U.S. Fish and Wildlife Service. 1996. Endangered and threatened wildlife and plants;
review of plant and animal taxa that are candidates for listing as endangered or
threatened species. Federal Register 61(40):7596-7613.

U.S. Fish and Wildlife Service and U.S. Forest Service. 1979. Proposed and Recommended
Threatened and Endangered Plant Species of the Forest Service Rocky Mountain Region.

Wilken, D.H. and K. DeMott. 1983. A new species of Thalictrum (Ranunculaceae) from
western Colorado. Brittonia 35(2):156-158.

Wooten, E.O. and P.C. Standley. 1913. Descriptions of new plants preliminary to
a report upon the flora of New Mexico. Contributions from the U.S. National Herbarium
16:109-196.

Zwinger, A.H. and B.E. Willard. 1972. Land Above the Trees: A Guide to American
Alpine Tundra. University of Arizona Press, Tucson, AZ.

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